diff options
Diffstat (limited to 'libs/midi++2/mtc.cc')
-rw-r--r-- | libs/midi++2/mtc.cc | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/libs/midi++2/mtc.cc b/libs/midi++2/mtc.cc new file mode 100644 index 0000000000..19fdb1fabd --- /dev/null +++ b/libs/midi++2/mtc.cc @@ -0,0 +1,329 @@ +/* + Copyright (C) 2004 Paul Barton-Davis + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + + $Id$ +*/ + +#include <cstdlib> +#include <unistd.h> +#include <string> +#include <iostream> + +#include <midi++/types.h> +#include <midi++/parser.h> +#include <midi++/port.h> +#include <midi++/mmc.h> +#include <pbd/transmitter.h> + +using namespace std; +using namespace sigc; +using namespace MIDI; + +bool +Parser::possible_mtc (byte *sysex_buf, size_t msglen) +{ + byte fake_mtc_time[4]; + + if (msglen != 10 || sysex_buf[0] != 0xf0 || sysex_buf[1] != 0x7f || sysex_buf[3] != 0x01 || sysex_buf[4] != 0x01) { + return false; + } + + /* full MTC */ + + fake_mtc_time[0] = sysex_buf[8]; // frames + fake_mtc_time[1] = sysex_buf[7]; // minutes + fake_mtc_time[2] = sysex_buf[6]; // seconds + fake_mtc_time[3] = (sysex_buf[5] & 0x1f); // hours + + _mtc_fps = MTC_FPS ((sysex_buf[5] & 0x60) >> 5); // fps + + /* wait for first quarter frame, which could indicate forwards + or backwards ... + */ + + reset_mtc_state (); + + /* emit signals */ + + mtc (*this, &sysex_buf[1], msglen - 1); + mtc_time (fake_mtc_time, true); + mtc_status (MTC_Stopped); + + return true; +} + +void +Parser::reset_mtc_state () +{ + _mtc_forward = false; + _mtc_running = MTC_Stopped; + _mtc_locked = false; + expected_mtc_quarter_frame_code = 0; + memset (_mtc_time, 0, sizeof (_mtc_time)); + memset (_qtr_mtc_time, 0, sizeof (_mtc_time)); + consecutive_qtr_frame_cnt = 0; + last_qtr_frame = 0; +} + +void +Parser::process_mtc_quarter_frame (byte *msg) +{ + int which_quarter_frame = (msg[1] & 0xf0) >> 4; + + /* Is it an expected frame? + Remember, the first can be frame 7 or frame 0, + depending on the direction of the MTC generator ... + */ + +#if 0 + cerr << "MTC: (state = " << _mtc_running << ") " + << which_quarter_frame << " vs. " << expected_mtc_quarter_frame_code + << " consecutive ? " << consecutive_qtr_frame_cnt + << endl; +#endif + + if (_mtc_running == MTC_Stopped) { + + /* we are stopped but are seeing qtr frame messages */ + + if (consecutive_qtr_frame_cnt == 0) { + + /* first quarter frame */ + + if (which_quarter_frame != 0 && which_quarter_frame != 7) { + + last_qtr_frame = which_quarter_frame; + consecutive_qtr_frame_cnt++; + } + + // cerr << "first seen qframe = " << (int) last_qtr_frame << endl; + + return; + + } else if (consecutive_qtr_frame_cnt == 1) { + + /* third quarter frame */ + + // cerr << "second seen qframe = " << (int) which_quarter_frame << endl; + + if (last_qtr_frame < which_quarter_frame) { + _mtc_running = MTC_Forward; + } else if (last_qtr_frame > which_quarter_frame) { + _mtc_running = MTC_Backward; + } + + mtc_status (_mtc_running); + } + + switch (_mtc_running) { + case MTC_Forward: + if (which_quarter_frame == 7) { + expected_mtc_quarter_frame_code = 0; + } else { + expected_mtc_quarter_frame_code = which_quarter_frame + 1; + } + break; + + case MTC_Backward: + if (which_quarter_frame == 0) { + expected_mtc_quarter_frame_code = 7; + + } else { + expected_mtc_quarter_frame_code = which_quarter_frame - 1; + } + break; + + case MTC_Stopped: + break; + } + + } else { + + /* already running */ + +// for testing bad MIDI connections etc. +// if ((random() % 500) < 10) { + + if (which_quarter_frame != expected_mtc_quarter_frame_code) { + + consecutive_qtr_frame_cnt = 0; + +#ifdef DEBUG_MTC + cerr << "MTC: (state = " << _mtc_running << ") " + << which_quarter_frame << " vs. " << expected_mtc_quarter_frame_code << endl; +#endif + + /* tell listener(s) that we skipped. if they return + true, just ignore this in terms of it being an error. + */ + + if (1) { /* mtc_skipped () */ + + /* no error, reset next expected frame */ + + switch (_mtc_running) { + case MTC_Forward: + if (which_quarter_frame == 7) { + expected_mtc_quarter_frame_code = 0; + } else { + expected_mtc_quarter_frame_code = which_quarter_frame + 1; + } + break; + + case MTC_Backward: + if (which_quarter_frame == 0) { + expected_mtc_quarter_frame_code = 7; + + } else { + expected_mtc_quarter_frame_code = which_quarter_frame - 1; + } + break; + + case MTC_Stopped: + break; + } + +#ifdef DEBUG_MTC + cerr << "SKIPPED, next expected = " << expected_mtc_quarter_frame_code << endl; +#endif + return; + } + + /* go back to waiting for the first frame */ + + expected_mtc_quarter_frame_code = 0; + memset (_qtr_mtc_time, 0, sizeof (_qtr_mtc_time)); + + _mtc_running = MTC_Stopped; + _mtc_locked = false; + mtc_status (MTC_Stopped); + + return; + + } else { + + /* received qtr frame matched expected */ + consecutive_qtr_frame_cnt++; + + } + } + + /* time code is looking good */ + + switch (which_quarter_frame) { + case 0: // frames LS nibble + _qtr_mtc_time[0] |= msg[1] & 0xf; + break; + + case 1: // frames MS nibble + _qtr_mtc_time[0] |= (msg[1] & 0xf)<<4; + break; + + case 2: // seconds LS nibble + _qtr_mtc_time[1] |= msg[1] & 0xf; + break; + + case 3: // seconds MS nibble + _qtr_mtc_time[1] |= (msg[1] & 0xf)<<4; + break; + + case 4: // minutes LS nibble + _qtr_mtc_time[2] |= msg[1] & 0xf; + break; + + case 5: // minutes MS nibble + _qtr_mtc_time[2] |= (msg[1] & 0xf)<<4; + break; + + case 6: // hours LS nibble + _qtr_mtc_time[3] |= msg[1] & 0xf; + break; + + case 7: + + /* last quarter frame msg has the MS bit of + the hour in bit 0, and the SMPTE FPS type + in bits 5 and 6 + */ + + _qtr_mtc_time[3] |= ((msg[1] & 0x1) << 4); + _mtc_fps = MTC_FPS ((msg[1] & 0x6) >> 1); + break; + + default: + /*NOTREACHED*/ + break; + + } + + mtc_qtr (*this); /* EMIT_SIGNAL */ + + // mtc (*this, &msg[1], msglen - 1); + + switch (_mtc_running) { + case MTC_Forward: + if ((which_quarter_frame == 7)) { + + /* we've reached the final of 8 quarter frame messages. + store the time, reset the pending time holder, + and signal anyone who wants to know the time. + */ + + if (consecutive_qtr_frame_cnt >= 8) { + memcpy (_mtc_time, _qtr_mtc_time, sizeof (_mtc_time)); + memset (_qtr_mtc_time, 0, sizeof (_qtr_mtc_time)); + if (!_mtc_locked) { + _mtc_locked = true; + } + mtc_time (_mtc_time, false); + } + expected_mtc_quarter_frame_code = 0; + + } else { + expected_mtc_quarter_frame_code = which_quarter_frame + 1; + } + break; + + case MTC_Backward: + if (which_quarter_frame == 0) { + + /* we've reached the final of 8 quarter frame messages. + store the time, reset the pending time holder, + and signal anyone who wants to know the time. + */ + + if (consecutive_qtr_frame_cnt >= 8) { + memcpy (_mtc_time, _qtr_mtc_time, sizeof (_mtc_time)); + memset (_qtr_mtc_time, 0, sizeof (_qtr_mtc_time)); + if (!_mtc_locked) { + _mtc_locked = true; + } + mtc_time (_mtc_time, false); + } + + expected_mtc_quarter_frame_code = 7; + + } else { + expected_mtc_quarter_frame_code = which_quarter_frame - 1; + } + break; + + default: + break; + } + +} |